Maintenance of appliances may be necessary when a part is worn and needs replacing. Or maintenance may be necessary from the hygienic standpoint, if particles of food have gotten into the appliance during previous use, and need to be cleaned out. Processing appliances are intended for the hotel and restaurant industry and also for family or domestic use. Here, food refers to food in the form of liquids and/or in the form of particles. Food also refers to any type of preparation based on edible or inedible products. Inedible products refers to cosmetic or any other type of preparation. Accordingly, processing appliances can also be intended for use in the pharmaceutical or cosmetic industry, or any other type of industry liable to need such an appliance.
One such appliance has a drive shaft, a hollow tube, a bell-shaped housing and a rotary tool. The shaft is inserted through the tube and, at one end is connected to an electric motor driving the shaft in rotation and at an opposite end is connected to the rotary tool. The rotary tool is placed in a position corresponding to the bell-shaped housing. The bell-shaped housing may be removably assembled in a sealing manner onto the tube, and in particular, makes it possible to prevent the tool from touching the bottom or the wall of a recipient, and allows the material to be worked.
The bell-shaped housing forms a small portion compared to the tube that forms a large portion. The bell-shaped housing is generally one third to one quarter smaller in size than the tube. The tube and the bell-shaped housing form an overall length that is measured along the tube lengthwise axis. The lengthwise axis is the rotation axis of the appliance about which the tool is put into rotation. The tube and bell-shaped housing are designed for immersion into a food preparation to be processed, over a length corresponding to approximately two thirds of the total length, with the bell-shaped housing totally immersed in the preparation.
Patent No. EP 0 925 010 B1 describes such an appliance that includes a stem, a cylindrical bearing placed between the bell-shaped housing and the stem, a sealing means placed on the bearing, and an elastic bellows placed to bear against the stem and connected to the sealing means. The bearing enhances guidance and rotation of the stem with respect to the tube of the appliance. The bellows ensures that the appliance is tight. However, this type of appliance does represent drawbacks. In particular, when it is necessary to clean the appliance, extracting the stem from the bell-shaped housing may cause a deterioration of the bellows, and cleaning the inside of the bearing with a tool, for instance, a knife, can also cause damage to the bearing.